n/exports-style | Bun Docs

A CommonJS file can export through module.exports or through its shorthand exports. Both start as the same object, but once you assign a new value to module.exports, anything you add to exports is no longer exported. Sticking to one of the two everywhere avoids that.

Configure#

Off by default. To turn it on:

bunfig.toml

[lint.rules]
"n/exports-style" = "error" # or "warn"

Every option, set to its default:

bunfig.toml

[lint.rules]
"n/exports-style" = [
  "error",
  "module.exports", # "module.exports" or "exports"
  {
    allowBatchAssign = false,
  },
]

Examples#

example.js1 problem

exports.parse = function parse(text) {
  return JSON.parse(text);
};

example.jsNo problems

module.exports.parse = function parse(text) {
  return JSON.parse(text);
};

Options#

bunfig.toml

[lint.rules]
"n/exports-style" = ["error", "exports", { allowBatchAssign = true }]

Option	What it does
`"module.exports"` (default)	Report every use of `exports`.
`"exports"`	Report every use of `module.exports`, and every assignment to `exports` itself.

The second option is an object:

Option	Default	What it does
`allowBatchAssign`	`false`	Allow one statement that assigns to both, such as `module.exports = exports = value`.

With "exports":

example.jswith "exports"2 problems

module.exports = { parse };
exports = { parse };

example.jswith "exports"No problems

exports.parse = parse;

With allowBatchAssign, you can replace the exported object and keep exports pointing at it:

example.jswith "exports", { "allowBatchAssign": true }No problems

module.exports = exports = function parse(text) {};
exports.version = "1.0.0";

example.jswith "exports"2 problems

module.exports = exports = function parse(text) {};
exports.version = "1.0.0";